Multi-level swim fin

Abstract

A swim fin having a shoe and an integrally connected bi-level, relatively short fin assembly. The fin assembly includes upper and lower levels connected by side walls. Automatic valve flaps are provided at the outer portions of baffles and pivot about transverse axes. The valves automatically open and close during the kick to change the apparent area of the assembly. The bi-level arrangement increases the overall efficiency of the swim fin during use.

What is claimed is: 
     
       1. A swim fin assembly comprising: a shoe having a toe portion; a multi-level fin assembly connected to said toe portion, each level of said assembly including a fin having an apparent area in the water; and automatic valve means associated with each of said levels for maximizing said apparent area during upward strokes of said fin assembly in the water and for minimizing said apparent area during downward strokes thereof. 
     
     
       2. The swim fin assembly of claim 1 wherein said fins are vertically spaced, and further including opposite side wall means for attaching said fins to one another. 
     
     
       3. The swim fin assembly of claim 2 wherein each of said fins includes a plurality of outwardly extending fin means having opposite side edges; and stiffener means for attaching adjacent ones of said side edges to one another. 
     
     
       4. The swim fin assembly of claim 3 wherein the connection between said fin assembly and said shoe is provided with weakened sections to allow limited flexure of said fin assembly relative to said shoe. 
     
     
       5. The swim fin assembly of claim 1 wherein each of said valve means comprises a generally rectangular member arranged for flexing movement about an axis that is transverse to a respective fin. 
     
     
       6. The swim fin assembly of claim 5 wherein each of said generally rectangular members extends outwardly of said axis a substantial distance to where its trailing edge is located at approximately the mid-point of the length of each of said fins. 
     
     
       7. A swim fin assembly comprising: a shoe having a toe portion; a fin assembly having upper and lower levels, each of said levels having a pair of fin members; means for connecting only said lower level to said toe portion; and substantially planar side wall means for attaching said upper and lower levels of fin members to one another in vertically spaced relationship. 
     
     
       8. The swim fin assembly of claim 7 wherein said fin assembly has a length that is approximately the same as the length of said shoe. 
     
     
       9. The swim fin assembly of claim 8 further including valve means associated with at least one of said levels of fin members for changing the apparent area during selected portions of a swimmer's kick.